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目录
SD卡无法识别问题定位
设备树确认mmc1 启用
驱动文件 sdhci-ss524v100.c 寄存器以及值的定义
probe函数匹配
通过函数的层层打印，sd卡寄存器读取出来时没有插上的状态
SD卡无法识别问题定位
硬件平台：ss524处理器，
内核版本:4.19.90
设备树确认mmc1 启用
mmc1: SD@0x10020000 {compatible = "vendor,sdhci";reg = <0x10020000 0x1000>;interrupts = <GIC_SPI 63 IRQ_TYPE_LEVEL_HIGH>;clocks = <&clock SS524V100_MMC0_CLK>;clock-names = "mmc_clk";resets = <&clock 0x34c0 16>, <&clock 0x34c4 1>;reset-names = "crg_reset", "dll_reset";max-frequency = <50000000>;crg_regmap = <&clock>;iocfg_regmap = <&iocfg_ctrl>;bus-width = <4>;cap-sd-highspeed;disable-wp;no-sdio;devid = <1>;status = "disabled";};
&mmc1 {status = "okay";
};
驱动文件 sdhci-ss524v100.c 寄存器以及值的定义
#include "sdhci-bsp.h"
#include "mci_proc.h"#define PERI_CRG_MMC_DRV_DLL 0x34c8
#define CRG_DRV_PHASE_SEL_SHIFT 15
#define CRG_DRV_PHASE_SEL_MASK (0x1F << 15)#define PERI_CRG_MMC_STAT 0x34d8
#define CRG_SAM_DLL_READY BIT(12)
#define CRG_DS_DLL_READY BIT(10)
#define CRG_P4_DLL_LOCKED BIT(9)/* MMC IO */
#define REG_MMC_CLK_IO 0xc8
#define REG_MMC_CMD_IO 0xcc
#define REG_MMC_D0_IO 0xd0
#define REG_MMC_D1_IO 0xd4
#define REG_MMC_D2_IO 0xd8
#define REG_MMC_D3_IO 0xdc
#define REG_MMC_D4_IO 0xec
#define REG_MMC_D6_IO 0xf0
#define REG_MMC_D5_IO 0xe0
#define REG_MMC_D7_IO 0xe4
#define REG_MMC_DQS_IO 0xf4
#define REG_MMC_RST_IO 0xc4#define REG_SD_PWR_EN_IO 0xc4
#define REG_SD_DETECT_IO 0xfc/* IO CFG */
#define IO_CFG_DRV_STR_MASK (0xf << 4)
#define io_cfg_drv_str_sel(str) ((str) << 4)
#define IO_CFG_PULL_UP BIT(8)
#define IO_CFG_PULL_DOWN BIT(9)
#define IO_CFG_SR BIT(10)
#define IO_CFG_SDIO_MASK (IO_CFG_DRV_STR_MASK | IO_CFG_PULL_UP | \IO_CFG_PULL_DOWN | IO_CFG_SR)
#define IO_CFG_SDIO_MUX 0x2
#define IO_CFG_EMMC_MUX 0x1
#define IO_CFG_MUX_MASK 0xF
#define MMC_BUS_WIDTH_8_BIT 8
#define MMC_BUS_WIDTH_4_BIT 4#define REG_SYSSTAT 0x11020018
#define BOOT_MEDIA_NAND BIT(2)
#define EMMC_BOOT_8BIT BIT(11)
#define BOOT_FLAG_MASK (0x3 << 2)
sdhci_bsp_parse_dt//pin mux set
bsp_mmc_io_mux_configsdhci_bsp_pltfm_initsdhci_bsp_set_clockint sdhci_bsp_parse_dt(struct sdhci_host *host)
{struct sdhci_bsp_priv *priv = sdhci_get_pltfm_priv(host);struct device_node *np = host->mmc->parent->of_node;u32 bus_width;int ret;ret = mmc_of_parse(host->mmc);if (ret)return ret;#ifdef CONFIG_MMC_CQHCIif (of_get_property(np, "mmc-cmd-queue", NULL))host->mmc->caps2 |= MMC_CAP2_CQE | MMC_CAP2_CQE_DCMD;
#endifif (of_get_property(np, "mmc-broken-cmd23", NULL))host->quirks2 |= SDHCI_QUIRK2_HOST_NO_CMD23;if (of_property_read_u32(np, "bus-width", &bus_width) == 0) {priv->bus_width = bus_width;} else {pr_err("%s: \"bus-width\" property is missing, assuming 1 bit.\n",mmc_hostname(host->mmc));priv->bus_width = 1;}if (of_get_property(np, "sdhci,1-bit-only", NULL) ||(priv->bus_width == 1)) {priv->bus_width = 1;host->quirks |= SDHCI_QUIRK_FORCE_1_BIT_DATA;}return 0;
}static const struct of_device_id sdhci_bsp_match[] = {{ .compatible = "vendor,sdhci" },{},
};MODULE_DEVICE_TABLE(of, sdhci_bsp_match);static struct sdhci_ops sdhci_bsp_ops = {.platform_execute_tuning = sdhci_bsp_execute_tuning,.reset = sdhci_reset,.set_clock = sdhci_bsp_set_clock,.set_bus_width = sdhci_set_bus_width,.set_uhs_signaling = sdhci_bsp_set_uhs_signaling,.hw_reset = sdhci_bsp_hw_reset,
#if defined(CONFIG_ARCH_SS318V100) || defined(CONFIG_ARCH_SS919V100) || \defined(CONFIG_ARCH_SS918V100) || defined(CONFIG_ARCH_SS015V100) || \defined(CONFIG_ARCH_SS013V100) || defined(CONFIG_ARCH_SS928V100) || \defined(CONFIG_ARCH_SS000V100).start_signal_voltage_switch = sdhci_bsp_start_signal_voltage_switch,
#endif.init = sdhci_bsp_extra_init,
};static const struct sdhci_pltfm_data sdhci_bsp_pdata = {.ops = &sdhci_bsp_ops,.quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL,.quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
};
probe函数匹配
static int sdhci_bsp_probe(struct platform_device *pdev)
{struct sdhci_host *host = NULL;const struct sdhci_pltfm_data *pdata = NULL;int ret;#ifdef CONFIG_MMC_CQHCIif (of_get_property(pdev->dev.of_node, "mmc-cmd-queue", NULL))pdata = &sdhci_bsp_cqe_pdata;elsepdata = &sdhci_bsp_pdata;
#elsepdata = &sdhci_bsp_pdata;
#endifhost = sdhci_pltfm_init(pdev, pdata, sizeof(struct sdhci_bsp_priv));if (IS_ERR(host))return PTR_ERR(host);ret = sdhci_bsp_pltfm_init(pdev, host);if (ret)goto pltfm_free;if (bsp_support_runtime_pm(host)) {pm_runtime_get_noresume(&pdev->dev);pm_runtime_set_autosuspend_delay(&pdev->dev, BSP_MMC_AUTOSUSPEND_DELAY_MS);pm_runtime_use_autosuspend(&pdev->dev);pm_runtime_set_active(&pdev->dev);pm_runtime_enable(&pdev->dev);}ret = sdhci_bsp_add_host(host);if (ret)goto pm_runtime_disable;if (bsp_support_runtime_pm(host)) {pm_runtime_mark_last_busy(&pdev->dev);pm_runtime_put_autosuspend(&pdev->dev);}return 0;pm_runtime_disable:if (bsp_support_runtime_pm(host)) {pm_runtime_disable(&pdev->dev);pm_runtime_set_suspended(&pdev->dev);pm_runtime_put_noidle(&pdev->dev);}pltfm_free:sdhci_pltfm_free(pdev);return ret;
}通过函数的层层打印，sd卡寄存器读取出来时没有插上的状态
static int sdhci_get_cd(struct mmc_host *mmc)
{struct sdhci_host *host = mmc_priv(mmc);int gpio_cd = mmc_gpio_get_cd(mmc);if (host->flags & SDHCI_DEVICE_DEAD)return 0;/* If nonremovable, assume that the card is always present. */if (!mmc_card_is_removable(host->mmc))return 1;/** Try slot gpio detect, if defined it take precedence* over build in controller functionality*/if (gpio_cd >= 0)return !!gpio_cd;/* If polling, assume that the card is always present. */if (host->quirks & SDHCI_QUIRK_BROKEN_CARD_DETECTION)return 1;/* Host native card detect */return 1;//!!(sdhci_readl(host, SDHCI_PRESENT_STATE) & SDHCI_CARD_PRESENT);
}最终问题是，SD卡检测引脚硬件的选择与软件的配置不是同一个引脚。
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